The present invention relates to an apparatus that adjusts operating parameters of railroad vehicles while moving along a track, and more specifically, to an apparatus that adjusts the rail pressure exerted by railroad vehicles moving along a track based on the curvature of the track.
In the railroad industry, railcar movers are used to move and connect railcars to each other and between locomotives. The railcar movers, which are configured with two sets of wheels (one set of steel wheels and one set of rubber wheels) to travel on both roads and railroad tracks, include couplers to connect to and move small numbers of rail cars around in a rail yard or other similar location. Railcar movers are preferred by railroad operators for these operations because they are less expensive than a locomotive, more convenient and less costly than paying the railroad operator to do the switching, easier and more productive than manually moving the railcars, and are more versatile since these vehicles can travel on road wheels to the railcars that need to be moved, instead of requiring a clear railroad track. Further, railcar movers are typically smaller than locomotives, which allows them to quickly and easily maneuver and move around obstacles at a rail yard to access the rail cars.
The configuration of the railroad track that the railcar movers travel on varies based on terrain. For example, the railroad track may have a steep incline or decline in mountainous areas or be generally level when on flat ground. Additionally, railroad track includes combinations of straight portions and curves to accommodate obstacles such as buildings, mountains, trees and the like, to pass through tunnels and to move rail cars to a particular location such as a shipping dock.
Locomotives that travel on railroad track are sufficiently large and heavy to maintain consistent pressure between the wheels and the rails of the track during movement through curves to help prevent the wheels of the locomotive and the railcars from riding up on the rails, i.e., rail climb, and derailing the locomotive and/or railcars. Railcar movers are smaller and lighter than locomotives and therefore are more susceptible to rail climb on the rails during the maneuvering of one or more larger and heavier rail cars, and particularly when moving through curves in the track.
Formulas, such as the Nadal and Wagner formulas, are well known in the railroad industry for determining wheel climb. These formulas are specific to the geometry of each rail vehicle and require advance knowledge of the configuration and dimensional parameters of the railroad track that the rail vehicles will be travelling on. As such, this method of determining wheel climb for rail vehicles is burdensome and time-consuming.
Thus, there is a need for an apparatus for rail movers that automatically adjusts the operating parameters of a rail mover to overcome wheel climb and maintain stability of the rail mover while traversing a railroad track.